scholarly journals Investigation of spray agglomeration process in continuously operated horizontal fluidized bed

2018 ◽  
Author(s):  
J. Du ◽  
A. Bück ◽  
E. Tsotsas
Keyword(s):  
Steady State ◽  
Fluidized Bed ◽  
Air Temperature ◽  
Food Industry ◽  
Continuous Process ◽  
Methyl Cellulose ◽  
Important Process ◽  
Agglomeration Process ◽  
Water Based ◽  
Bed Agglomeration

Spray fluidized bed agglomeration is an important process in particle formation and is widely used in the chemical, pharmaceutical and food industry. In this study a continuously operated horizontal fluidized bed is employed to obtain a continuous agglomeration process. It is conducted with glass beads (dst=200 µm) and water-based binder hydroxy-propyl-methyl-cellulose (HPMC) sprayed by three top nozzles. The steady state is reached and samples are taken periodically and analyzed. The influence of fluidization air temperature and configurations of internal weirs are studied. Keywords: horizontal fluidized bed, spray agglomeration, continuous process

scholarly journals Agglomeration process in the fluidized bed, the effecting parameters and some applications

2018 ◽  
Vol 13 (3-4) ◽  
pp. 159-163
Author(s):  
Hira Yuksel ◽  
Nur Dirim
Keyword(s):  
Heat Transfer ◽  
Fluidized Bed ◽  
Air Temperature ◽  
Mechanical Resistance ◽  
High Porosity ◽  
Air Velocity ◽  
Mixing Rate ◽  
Agglomeration Process ◽  
Mass And Heat Transfer ◽  
Bed Agglomeration

The agglomeration process has been commonly used to improve the functional properties of powder products to form larger agglomerates. Agglomeration provides a granular structure to powders, reduce the dusting and improving their characteristics, such as storage stability, wettability, dispersibility, and solubility. This process can be performed by different methods, one of which is fluidized bed agglomeration widely used in food processing since the agglomerates produced by this technique have high porosity, low density, and good mechanical resistance. At the same time, this process is influenced by many factors; e.g., inlet air temperature, air velocity, mixing rate, and properties of the binder agents. Inlet air temperature affects the mass and heat transfer; air velocity prevents caking and accelerates mass and heat transfer; mixing rate allows mixing the binder agent uniformly over the particles; and the properties of the binder agent, such as concentration and viscosity have an impact on the properties of the final product. These four factors should be well known and controlled so that the agglomerates produced have the desired properties. Furthermore, the use of fluidized bed agglomeration results in products that can be used in widespread areas and in high quantities, and this method also creates the opportunity to utilize excess foods not consumed.

Investigation of Ash-Related Issues During Combustion of Maize Straw and Wood Biomass Blends in Lab-Scale Bubbling Fluidized Bed Reactor

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Krzysztof Głód ◽  
Janusz Lasek ◽  
Krzysztof Słowik ◽  
Jarosław Zuwała ◽  
Daniel Nabagło ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Air Velocity ◽  
Interesting Phenomenon ◽  
Simultaneous Application ◽  
Agglomeration Process ◽  
Bubbling Fluidized Bed ◽  
Bed Agglomeration ◽  
The Cost ◽  
The Impact ◽  
Combustion Of Solid Fuels

Abstract During the combustion of solid fuels, the undesired effects of ash transformation include bed agglomeration, slagging, and fouling processes. In particular, a problematic consequence of bed agglomeration is the defluidization process, resulting from the disappearance of gaseous bubbles that are created behind air distributors. Different solutions can be applied against the agglomeration process. One possible method is to apply some additives that influence the ash behavior, thus inhibiting the agglomeration process. This paper presents the results of investigations into ash-related issues in a laboratory-scale bubbling fluidized bed (BFB) reactor. In particular, the impact of additives (kaolin, halloysite, fly ash, and the residuals from wet desulfurization system (IMOS)) on bed agglomeration was investigated. It was found that the addition of these compounds increased the defluidization time from ∼109 min (without additive) to ∼285 min in the BFB (with the addition of 0.1 g/min of kaolin). The morphology of additive (kaolin and halloysite) transformation after their addition into the combustion chamber was discussed. Another interesting phenomenon is that residuals from the IMOS exhibited the ability to be an additive against the agglomeration process. The defluidization time can be also significantly increased by the simultaneous application of the additive and the control of fluidization air velocity. The procedure of periodical bed moving by impulse primary air feeding against defluidization (PADM) is suggested and discussed. The PADM procedure resulted in a 36% reduction of additive, thus reducing the cost of measures against ash-related issues.

scholarly journals Influence of drying conditions on process properties and parameter identification for continuous fluidized bed spray agglomeration

2018 ◽  
Author(s):  
Gerd Strenzke ◽  
Ievgen Golovin ◽  
Maximilian Wegner ◽  
Stefan Palis ◽  
Andreas Bück ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Feed Rate ◽  
Continuous Process ◽  
Binder Content ◽  
Balance Model ◽  
Process Stability ◽  
Primary Particles ◽  
Bed Agglomeration ◽  
Drying Conditions ◽  
Population Balances

Agglomeration is a particle formulation process in which at least two primary particles are combined to form a new one. The growth of agglomerates depends on interactions of particles covered with wet spots that generated by depositions of binder droplets. This work experimentally compares the influence of external feed rate and sprayed binder content on product properties and process stability with internal separation at different drying conditions. Due to the identification of parameters a populations balance model (PBM) is developed. The PBM includes the agglomeration kernel function, which characterizes the kinetics, i.e. the rate at which primary particles build agglomerates. Keywords: spray fluidized bed agglomeration; drying; continuous process; internal separation; population balances

Agglomerated mushroom ( Agaricus bisporus ) powder: Optimization of top spray fluidized bed agglomeration conditions

2021 ◽  
Author(s):  
İlyas Atalar ◽  
Abdullah Kurt ◽  
Furkan Türker Saricaoğlu ◽  
Osman Gül ◽  
Hüseyin Gençcelep
Keyword(s):  
Fluidized Bed ◽  
Agaricus Bisporus ◽  
Bed Agglomeration

scholarly journals Mitigating bed agglomeration in a fluidized bed gasifier operating on rice straw

2020 ◽  
Vol 6 ◽  
pp. 275-285
Author(s):  
Jurarat Nisamaneenate ◽  
Duangduen Atong ◽  
Anun Seemen ◽  
Viboon Sricharoenchaikul
Keyword(s):  
Fluidized Bed ◽  
Rice Straw ◽  
Fluidized Bed Gasifier ◽  
Bed Agglomeration

Preparation and application of water-based nano-silver conductive ink in paper-based 3D printing

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Chenfei Zhao ◽  
Jun Wang ◽  
Lini Lu
Keyword(s):  
Flexible Electronics ◽  
Low Cost ◽  
Methyl Cellulose ◽  
Conductive Ink ◽  
Content Type ◽  
Nano Silver ◽  
Printed Circuit ◽  
Silver Ink ◽  
Sintering Time ◽  
Water Based

Purpose In flexible electronics applications, organic inks are mostly used for inkjet printing. Three-dimensional (3 D) printing technology has the advantages of low cost, high speed and good precision in modern electronic printing. The purpose of this study is to solve the high cost of traditional printing and the pollution emissions of organic ink. It is necessary to develop a water-based conductive ink that is easily degradable and can be 3 D printed. A nano-silver ink printed circuit pattern with high precision, high conductivity and good mechanical properties is a promising strategy. Design/methodology/approach The researched nano-silver conductive ink is mainly composed of silver nanoparticles and resin. The effect of adding methyl cellulose on the ink was also explored. A simple 3 D circuit pattern was printed on photographic paper. The line width, line length, line thickness and conductivity of the printed circuit were tested. The influence of sintering temperature and sintering time on pattern resistivity was studied. The relationship between circuit pattern bending performance and electrical conductivity is analyzed. Findings The experimental results show that the ink has the characteristics of low silver content and good environmental protection effect. The printing feasibility of 3 D printing circuit patterns on paper substrates was confirmed. The best printing temperature is 160°C–180°C, and the best sintering time is 30 min. The circuit pattern can be folded 120°, and the cycle is folded more than 60 times. The minimum resistivity of the circuit pattern is 6.07 µΩ·cm. Methyl cellulose can control the viscosity of the ink. The mechanical properties of the pattern have been improved. The printing method of 3 D printing can significantly reduce the sintering time and temperature of the conductive ink. These findings may provide innovation for the flexible electronics industry and pave the way for alternatives to cost-effective solutions. Originality/value In this study, direct ink writing technology was used to print circuit patterns on paper substrates. This process is simple and convenient and can control the thickness of the ink layer. The ink material is nonpolluting to the environment. Nano-silver ink has suitable viscosity and pH value. It can meet the requirements of pneumatic 3 D printers. The method has the characteristics of simple process, fast forming, low cost and high environmental friendliness.

scholarly journals Temperature uniformity in the CERN CLOUD chamber

2017 ◽  
Vol 10 (12) ◽  
pp. 5075-5088 ◽  
Author(s):  
António Dias ◽  
Sebastian Ehrhart ◽  
Alexander Vogel ◽  
Christina Williamson ◽  
João Almeida ◽  
...  
Keyword(s):  
Steady State ◽  
Air Temperature ◽  
Elevated Temperatures ◽  
Trace Gases ◽  
Vertical Direction ◽  
Cloud Chamber ◽  
Temperature Uniformity ◽  
Atmospheric Conditions ◽  
Cloud Droplets ◽  
Experimental Conditions

Abstract. The CLOUD (Cosmics Leaving OUtdoor Droplets) experiment at CERN (European Council for Nuclear Research) investigates the nucleation and growth of aerosol particles under atmospheric conditions and their activation into cloud droplets. A key feature of the CLOUD experiment is precise control of the experimental parameters. Temperature uniformity and stability in the chamber are important since many of the processes under study are sensitive to temperature and also to contaminants that can be released from the stainless steel walls by upward temperature fluctuations. The air enclosed within the 26 m3 CLOUD chamber is equipped with several arrays (strings) of high precision, fast-response thermometers to measure its temperature. Here we present a study of the air temperature uniformity inside the CLOUD chamber under various experimental conditions. Measurements were performed under calibration conditions and run conditions, which are distinguished by the flow rate of fresh air and trace gases entering the chamber at 20 and up to 210 L min−1, respectively. During steady-state calibration runs between −70 and +20 °C, the air temperature uniformity is better than ±0.06 °C in the radial direction and ±0.1 °C in the vertical direction. Larger non-uniformities are present during experimental runs, depending on the temperature control of the make-up air and trace gases (since some trace gases require elevated temperatures until injection into the chamber). The temperature stability is ±0.04 °C over periods of several hours during either calibration or steady-state run conditions. During rapid adiabatic expansions to activate cloud droplets and ice particles, the chamber walls are up to 10 °C warmer than the enclosed air. This results in temperature differences of ±1.5 °C in the vertical direction and ±1 °C in the horizontal direction, while the air returns to its equilibrium temperature with a time constant of about 200 s.

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